Coffee-grinder.



W. A. MOGUIRE.

COFFEE GRINDER.

APPLICATION FILED JULY 5, 1911.

1 ,034,8 1 3. Patented Aug. 6, 1912.

2 SHEETSSHEET 1.

COLUMBIA PLANOGRAPH 001, WASHINGTON. D, c.

W. A. McGUIRE.

COFFEE GRINDER.

APPLICATION FILED JULY 5, 1911.

1,034,81 3. Patented 6, 1912.

2 SEE SHBET 2.

WILLIAM A. MOGUIRE, OF TURTLE CREEK, PENNSYLVANIA.

COFFEE-GRINDER.

Specification of Letters Patent.

Patented Aug. 6, 1912.

Application filed July 5, 1911. Serial No. 637,028.

T 0 all whom it may concern:

Be it known that I, WILLIAM A. Mo- GUIRE, a citizen of the UnitedStates, residing at Turtle Creek, in the county of Allegheny and Stateof Pennsylvania, have invented a new and useful Coffee-Grinder, of whichthe following is a specification.

This invention has reference to improvements in coffee grinders,although not necessarily limited to such specific use, and its object isto provide a grinder or mill capable of grinding coffee or the like morerapidly than mills of the more common type.

The invention comprises two grinding rolls, between which the coffee isfed, which rolls may be brought into suitable relation depending uponthe desired fineness of the ground product, the axes of rotation of thetwo rolls being substantially parallel. One roll or grinder is providedwith circumferential series of ridges, preferably of V-shape in parallelrelation one to the other and having their outer edges formed intoteeth, while the other roll or grinder is provided with likecircumferential ridges, which, however, are not continuous peripherally,but are divided by a circular series of channels preferablyequi-distantly spaced about the roll or grinder, and each of a depthabout that of the circumferential grooves between=the ridges anddefining the latter. The first mentioned grooves extend in the generaldirection of the length of the axes of rotation of the roll or grinderin which they are formed, but are displaced so as to form a small angleto a respective radial axial plane of the roll or grinder, so that eachgroove defines a screw of long pitch making but a small fraction of aturn about the axis of rotation from one end of the roll to the other.The rolls or grinders are mounted in a suitable support, so that oneroll or grinder may be adjusted toward or from the other roll or grinderwith the circumferential ridges of one roll presented to the groovesbetween the ridges of the other roll, the ridges of the two rollsoperating as coacting grinding or crushing members, whereby on therotation of the grinders the coffee berries presented to these grindersare engaged by the respective ridges and broken and crushed to thedesired fineness, the degree of fineness being determined by thecloseness of approach of the rolls one toward the other.

The invention will be best understood from a consideration of thefollowing detailed description, taken in connection with theaccompanying drawings forming a part of this specification, with theunderstanding, however, that while the drawings show a practical form ofthe invention, the latter is not limited to such form, but issusceptible of various modifications and changes so long as such changesmark no material departure from the scope of the invention.

In the drawings :Figure 1 is a side elevation of a coffee mill as viewedfrom the side remote from the handle. Fig. 2 is a central verticalsection of the structure shown in Fig. 1 on a plane approximately midwayof the length of the grinding rolls. Fig. 3 is a section on the line 33of Fig. 1 with remoter parts omitted. Fig. 4 is a perspective view of anadjusting device for one of the grinding rollers. Fig. 5 is a plan viewof the longitudinally grooved grinding roll. Fig. 6 is a similar view ofthe other grinding roll.

Referring to the drawings, there is shown a body member 1 designed toreceive the coffee to be ground, and for convenience of description itwill be assumed that the material to be ground is coffee without,however, limiting the use of the invention to such particular material.The body member 1 terminates in a hopper 2 and to this hopper there issecured a casing 3 by brackets 4 or in any other suitable manner, andthis casing in turn terminates in a hopper 5. The hopper 2 has adischarge opening 6 and the hopper 5 has a discharge opening 7. Thestructures so far described are to be taken as more or less indicativeof any suitable structures for the purposes of the invention, sincethese particular structures may be greatly modified without in anymanner affecting the invention.

Lodged within the casing 3 are two rollers 8 and 9, respectively, eachformed at the ends with axial pintles 10, 11, respectively. The pintles10 extend. through elongated slots 12 formed in the side Walls of theeasing 3, while the pintles 11 may be journaled directly in the casing3, as indicated in Figs. 1 and 3. Because of the slots 12 the pintles 10which extend into and if desired through these slots, may move along theslots in the direction of their length, whereby, the slots 12 beingproperly directed, the roll or grinder 8 may be moved toward and fromthe roll or grinder 9. Either of the rolls or grinders may have one ofits pintles sutliciently extended to provide for the application of adriving means, and in the particular showing of the drawings one of thepintles 10 is so extended and receives a crank handle 13, whereby theroller 8may be rotated at the will of an operator. In coffee grinders ormills of large capacity the handle 13 is replaced by other power applying means, such as are commonly used in connection with powergrinders, but this forms no part of the present invention and is,therefore, not illustrated.

lVithin the casing 3 there is a frame 14 separately shown in Fig. 4, andthis frame is in the particular construction shown of U-form with thelegs 15 of the U parallel and the yoke of the U carrying a centrallylocated pin 16 projecting from the yoke in a direction opposite from thelegs 15 and carried through the corresponding wall of the casing 3. Thispin 16 is screw threaded and to it is applied a Wing nut 17. The purposeof the stem 16 and wing nut 17 is to provide for the adjustment of theframe 14 for a purpose which will presently appear. The pintles 11 ofthe roll or grinder 9 extend through the legs 15 of the frame 14, theselegs being provided with elongated notches or recesses 18 permittingmovement of the frame in the direction of the length of the legs 15without interference from engagement with the pintles 12, the notches 18being sufficiently elongated to permit all the movement of the frame 14desired without the ends of the recesses 18 engaging said pintles. Nearthe free ends the legs 15 have formed therein alined bearings 19, whichbearings are shown as open at one side, and in these bearings thepintles 10 of the roll or grinder 8 rest, and these pintles also mayengage the long Walls of the slots 12, so that the frame 14 does not ofnecessity carry the roller 8 at all. When the thumb nut 17 ismanipulated in the proper direction, the roller 8 is or may be movedaway from the roller 9 and when the thumb nut 17 is manipulated in theother direction the roller 8 is caused to approach the roller 9, thelatter being in fixed relation to the casing 3 other than its capabilityof rotat ing about its longitudinal axis, while the roller 8 is movableby the frame 14 with relation to the frame 3 to and from the roller 9.

In order that the coffee berries ,may be ground, the rollers are formedwith grinding devices, one roller being differently formed from theother, the grinding devices being formed on rather than attached to thegrinding rolls. The roller 8 has formed on its surface ridges or teeth20 of V shape with the apexes of the V outward, and these ridges orteeth are arranged in series extending in the general direction of thelongitudinal axis of the roller, while each longitudinal series ofridges or teeth is divided from the next longitudinal series of ridgesor teeth by a groove 21 also generally longitudinal of the roller and ofa depth about that of the height of the ridges or teeth. The teeth 20 ofeach series extend from one groove 21 to the other and the teeth of oneseries are in line with the corresponding teeth of all the other seriesentirely around the roller 8, so that the teeth form broken peripheralridges about the roller, the breaks in the ridges being due to thegrooves 21, which latter are substantially parallel one with the other,and, therefore, the longitudinal series of teeth 20 are alsosubstantially parallel one with the other, the grooves 21 and thelongitudinal series of teeth 20 being all of about the same widthcircumferentially, although this particular arrangement is notmandatory. Furthermore, the grooves 21 and the longitudinal series ofteeth 20 intermediate of these grooves do not extend strictly in thedirection of the longitudinal axis of the roller, but at a slight anglethereto, so that each groove and each longitudinal series of teeth has atwist approximately equivalent to its width, that is, one end of aseries of teeth is about opposite the other end of the ad joining groove21 in the line of the axis of the roller, each series of teeth thereinhaving a pitch throughout the length of the series, which is equal tothe length of the roller, approximately equal to the circumferentiallength of the individual teeth of the series. Furthermore, each toot-hof each series is provided with an intermediate notch 22 of less depththan the height of the tooth.

The roller or grinder 9 is provided with circumferential ridges 23 ofV-shape approximately agreeable in number and depth to the teeth 20 of alongitudinal series of teeth, and when the rollers are assembled theridges of one grinder may seat in the grooves within the ridges of theother grinder. The ridges 23 are unbroken circumferentially except thatin the outer edges of each there is formed a circumferential series ofnotches 24 sufficiently close to define short teeth of approximatelypyramidal form and substantially continuous throughout the length ofeach ridge 23.

The roller or grinder 8 has its surface provided with a circular seriesof teeth elongated circumferentially and arranged closely adjacent inlongitudinal series, the circumferentially disposed teeth beingseparated by grooves or spaces of about the same extent as the teethcircumferentially, and the longitudinal series of teeth, as well as thegrooves have a helical pitch substantially the same as the length of anindividual tooth, while each tooth has the continuity of its outer alledge broken intermediately by a notch. A roller or grinder 9 has on itssurface a longitudinal series of circumferential ridges, the outer edgesof which are notched to con stitute each a circular series of teeth ofless radial extent than the ridges, while the ridges of the roller 9 areadapted to engage between the outer edges of the teeth of the roller 8,whereby the active surfaces of the two rollers may be brought into veryclose relation for fine grinding, or may be suitablv separated forcoarse grinding.

hen coffee berries are introduced into the receptacle 1, they gravitateto the hopper 2 and from thence through the opening 6 to the rollers orgrinders 8 and 9 and seek the point where these grinders meet or havetheir surfaces close together. Now, by turning the roller 8 by means ofthe handle 1?), or by any other suitable means provided, the coffeeberries will tend to move into the grooves 21, which because of theirpitch are brought progressively throughout their length toward thecorresponding portion of the roll 9, and those edges of the teeth 20which may be called the forward edges because their ends are presentedtoward the direction of rotation, engage the berries and force them intocontact with the teeth 21 of the ridges 23. The constantly approachingsurfaces of the two rollers bring sufficient pressure to bear upon thecoffee berries to crush the latter, and because of the brittle nature ofsuch coffee berries they shatter into pieces, which in turn are caughtby the teeth and broken up into smaller pieces until finally the piecesare small enough to pass through the spaces between the two rollers andfinally reach the hopper to pass therefrom through the opening 7 into asuitable receptacle. It will be observed that the ridges 23 are alwayspresented in or opposite the grooves 21 and are always presented intraversing or operative relation to the spaces between the teeth 20, sothat no particles of coffee can pass between the rollers or grinderswithout being acted upon unless these particles have reached therequisite fineness. The teeth 20 because of the spacing due to thegrooves 21 act not only as crushing means together with the ridges 23,but the forward ends of these teeth operate as impelling means for thecoffee forcing the berries or broken particles of the berries positivelybetween the rollers without giving a chance for the particles to springback. This is in part due to the fact that those ends of the teeth 20which constitute the forward ends in the direction of rotation aresubstantially perpendicular to the sur face of the roller as defined bythe grooves 21 and, therefore, bite into the coffee berries or brokenpieces thereof and urge the material between the rollers with therapidity of rotation of the rollers.

Practical experience with the grinding rollers as compared with coffeegrinders as ordinarily constructed has shown a marked increase in thespeed of grinding, like quantities of coffee being ground by the rollersof the present invention in but a comparatively small fraction of timewith respect to the time taken by the ordinary grinders. The actualspeed of grinding shows that the grinders of the present invention willact upon a certain quantity of coffee in about one-sixth the time takenby grinders as ordinarily found on the market.

What is claimed isz '1. In a coffee grinder, a pair of grinding rollers,one roller having circumferential continuous ridges each with its outeredge formed into a circular series of teeth of less depth than theheight of the ridge, and the other roller being provided withcircumferential discontinuous ridges each provided between the points ofdiscontinuity with a plurality of teeth of less depth than the height ofthe ridge.

In a coffee grinder, a pair of grinding rollers, one roller havingcircumferentiall v continuous ridges each with its outer edge formedwith a circumferential series of teeth of less depth than the height ofthe ridge, and the other roller being provided with circumferentiallydiscontinuous ridges in the form of substantially longitudinallyarranged spaced series of teeth with the teeth elongatedcircumferentially, the teeth of each series being provided with anintermediate notch.

3. In a grinder, a pair of grinding rollers, one roller being providedwith an axial series of circumferential continuous parallel ridgesnarrowed outwardly and formed into teeth, and the other roller having alike series of ridges made circumferentially discontinuous by a circularseries of grooves in depth substantially the same as the height of theridges and in width substantially the same as the circumferential extentof the ridges between adjacent grooves.

4. In a coffee grinder, grinding rollers one provided with alongitudinal series of circumferential ridges of substantially V- shapewith the angle of the V outward and the outer edge of each ridge notchedto form a continuous circumferential series of teeth of less depth thanthe height of the ridges, and the other roller being provided withsubstantially longitudinal series of teeth spaced apartcircumferentially and each tooth elongated circumferentially andprovided with an intermediate notch of less depth than the height of thetooth, each series of teeth having a longitudinal pitch approximatelyequal to the width of the space separating the series from the nextadjacent series.

5. In a coffee grinder, a grinding roller formed with circumferentiallyarranged ridges of substantially V-shape in cross section, said ridgesbeing arranged in equally spaced longitudinal series having a pitch withrelation to the longitudinal axis of the roller substantially equal tothe space separating one longitudinal series from the next adjacent one.

(3. In a cotfee grinder, a grinding roller of substantially cylindricalt'orin having thereon a longitudinal series of closely relatedcircumterential ridges each formed at its apex with a continuous seriesof notches defining short teeth oi approximately pyramidal torm, andanother grinding roller having a longitudinal series of circumferentialridges divided by equally spaced longitudinally arranged grooves each ofa width substantially that of the portion of the ridges included betweentwo adjacent grooves, each ridge between two adjacent grooves beingFormed into teeth elongated circlnnferentially.

7. In a cottee grinder, a grinding roller fOl'l'lltPd with substantiallyequally spaced ltmgitudinal series of circumferentially extended teethof substantially V shape and each series of teeth being pitched withrelation to the longitudinal axis of the roller to an extentsubstantially that of the space separating such series from the nextadjacent series, each tooth being also provided with an intermediatenotch of less depth than the height of the respective tooth.

8. In a cottee grinder, a suitable casing, a grinding roller journaledin said casing, another grinding roller having hearings in the casingelongated in a direction toward the bearings of the first roller, and anadjusting member in the casing in embracing relation to the first namedroller and having bearings for the journals of the second named rollerand provided with elongated recesses for the passage of the journals ofthe first named roller, said adjusting member being provided withmanipulating means for moving said adjusting member and with it thesecond named roller toward and from the first named roller.

In testimony, that I claim the foregoing as my own, I have heretoafiixed my signa ture in the presence of two witnesses.

\VILLIAM A. MoGU IRF.

\Vitnesses:

M. \V. MoDoNALn, EDITH MULHOLLAJ.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

